A conventional lever switch of the category is shown in FIG. 13, a cross sectional front view, and FIG. 14, an exploded perspective view. A resin case 1 is shaped in the form of a box with the top face open. The opposing sidewalls are provided with round holes 1A, 1B at the upper part in a side portion. On the inner bottom surface, a common contact point 2 having a long size and an individual contact point 3 having a short size are provided. Each of the contact points 2, 3 has its respective terminal 2A, 3A provided at the outside of case 1.
A movable contact element 4 made of an elastic thin metal sheet comprises a flexed portion 4D bent in the shape of a character U in the middle, a fixed end 4A in one end and a contact portion, which is split into two contact points 4B, 4C, in the other end. The contact point 4B normally makes an elastic contact on the common contact point 2 disposed on the bottom surface of resin case 1, whereas the contact point 4C is positioned on the bottom resin surface at a place on the extension of short-sized individual contact point 3.
A resin lever 5 has in one end a rotation axis 5A, 5B to be fitting rotatably with the holes 1A, 1B and a protrusion 5C which is to have contact with the fixed end 4A; in the other end are an operating portion 5D protruding upward and a contact portion 5E which is to make contact with the upper surface of flexed portion 4D. The contact portion 5E is normally pushed up by the elastic force of the movable contact element 4 to be held at a certain position.
The operation of a lever switch having the above-described structure is described below. Shown in FIG. 13 is the lever switch in OFF state. When the operating portion 5D is pressed to the state of FIG. 15, a cross sectional view, the lever 5 rotates around the rotation axis 5A, 5B to push down and bend the flexed portion 4D. As a result, the contact portion 4B, 4C slides in the direction as indicated with a character X, until the contact portion 4C makes contact with the short-sized individual contact point 3. Thus the common contact point 2 and the individual contact point 3, or the terminal 2A and the terminal 3A, are electrically connected. The switch is brought to ON state. In the state of FIG. 15, as soon as the force pushing the operating portion 5D down is withdrawn the lever 5 is pushed back by the elastic restorative force of movable contact element 4. The switch returns to the OFF state as shown in FIG. 13.
The conventional lever switch smoothly responds to an action of pressing the lever 5 from the top and to a force exerted on the lever from the left as indicated by an arrow mark with a character Y in FIG. 13. However, the switch does not respond to an operation from the right side. In view of the increasingly complicated function of the recent electronic appliances, there is a strong need for a lever switch that smoothly responds to the operating forces from both the right and the left as well as to the pressing action from the top.